From: Jimmy Assarsson <extja@xxxxxxxxxx> Ensure statistics, error counters, and CAN state are updated consistently, even when alloc_can_err_skb() fails during state changes or error message frame reception. Signed-off-by: Jimmy Assarsson <extja@xxxxxxxxxx> Link: https://patch.msgid.link/20241230142645.128244-1-extja@xxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- .../net/can/usb/kvaser_usb/kvaser_usb_hydra.c | 124 +++++++----------- .../net/can/usb/kvaser_usb/kvaser_usb_leaf.c | 31 ++--- 2 files changed, 60 insertions(+), 95 deletions(-) diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c index 3764b263add3..5ec8b300bebf 100644 --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c @@ -926,6 +926,42 @@ kvaser_usb_hydra_bus_status_to_can_state(const struct kvaser_usb_net_priv *priv, } } +static void kvaser_usb_hydra_change_state(struct kvaser_usb_net_priv *priv, + const struct can_berr_counter *bec, + struct can_frame *cf, + enum can_state new_state) +{ + struct net_device *netdev = priv->netdev; + enum can_state old_state = priv->can.state; + enum can_state tx_state, rx_state; + + tx_state = (bec->txerr >= bec->rxerr) ? + new_state : CAN_STATE_ERROR_ACTIVE; + rx_state = (bec->txerr <= bec->rxerr) ? + new_state : CAN_STATE_ERROR_ACTIVE; + can_change_state(netdev, cf, tx_state, rx_state); + + if (new_state == CAN_STATE_BUS_OFF && old_state < CAN_STATE_BUS_OFF) { + if (priv->can.restart_ms == 0) + kvaser_usb_hydra_send_simple_cmd_async(priv, CMD_STOP_CHIP_REQ); + + can_bus_off(netdev); + } + + if (priv->can.restart_ms && + old_state >= CAN_STATE_BUS_OFF && + new_state < CAN_STATE_BUS_OFF) { + priv->can.can_stats.restarts++; + if (cf) + cf->can_id |= CAN_ERR_RESTARTED; + } + if (cf && new_state != CAN_STATE_BUS_OFF) { + cf->can_id |= CAN_ERR_CNT; + cf->data[6] = bec->txerr; + cf->data[7] = bec->rxerr; + } +} + static void kvaser_usb_hydra_update_state(struct kvaser_usb_net_priv *priv, u8 bus_status, const struct can_berr_counter *bec) @@ -951,41 +987,11 @@ static void kvaser_usb_hydra_update_state(struct kvaser_usb_net_priv *priv, return; skb = alloc_can_err_skb(netdev, &cf); - if (skb) { - enum can_state tx_state, rx_state; - - tx_state = (bec->txerr >= bec->rxerr) ? - new_state : CAN_STATE_ERROR_ACTIVE; - rx_state = (bec->txerr <= bec->rxerr) ? - new_state : CAN_STATE_ERROR_ACTIVE; - can_change_state(netdev, cf, tx_state, rx_state); - } - - if (new_state == CAN_STATE_BUS_OFF && old_state < CAN_STATE_BUS_OFF) { - if (!priv->can.restart_ms) - kvaser_usb_hydra_send_simple_cmd_async - (priv, CMD_STOP_CHIP_REQ); - - can_bus_off(netdev); - } - - if (!skb) { + kvaser_usb_hydra_change_state(priv, bec, cf, new_state); + if (skb) + netif_rx(skb); + else netdev_warn(netdev, "No memory left for err_skb\n"); - return; - } - - if (priv->can.restart_ms && - old_state >= CAN_STATE_BUS_OFF && - new_state < CAN_STATE_BUS_OFF) - priv->can.can_stats.restarts++; - - if (new_state != CAN_STATE_BUS_OFF) { - cf->can_id |= CAN_ERR_CNT; - cf->data[6] = bec->txerr; - cf->data[7] = bec->rxerr; - } - - netif_rx(skb); } static void kvaser_usb_hydra_state_event(const struct kvaser_usb *dev, @@ -1080,7 +1086,6 @@ kvaser_usb_hydra_error_frame(struct kvaser_usb_net_priv *priv, struct net_device_stats *stats = &netdev->stats; struct can_frame *cf; struct sk_buff *skb; - struct skb_shared_hwtstamps *shhwtstamps; struct can_berr_counter bec; enum can_state new_state, old_state; u8 bus_status; @@ -1097,51 +1102,22 @@ kvaser_usb_hydra_error_frame(struct kvaser_usb_net_priv *priv, &new_state); skb = alloc_can_err_skb(netdev, &cf); + if (new_state != old_state) + kvaser_usb_hydra_change_state(priv, &bec, cf, new_state); - if (new_state != old_state) { - if (skb) { - enum can_state tx_state, rx_state; + if (skb) { + struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb); - tx_state = (bec.txerr >= bec.rxerr) ? - new_state : CAN_STATE_ERROR_ACTIVE; - rx_state = (bec.txerr <= bec.rxerr) ? - new_state : CAN_STATE_ERROR_ACTIVE; - - can_change_state(netdev, cf, tx_state, rx_state); - - if (priv->can.restart_ms && - old_state >= CAN_STATE_BUS_OFF && - new_state < CAN_STATE_BUS_OFF) - cf->can_id |= CAN_ERR_RESTARTED; - } - - if (new_state == CAN_STATE_BUS_OFF) { - if (!priv->can.restart_ms) - kvaser_usb_hydra_send_simple_cmd_async - (priv, CMD_STOP_CHIP_REQ); - - can_bus_off(netdev); - } - } - - if (!skb) { - stats->rx_dropped++; - netdev_warn(netdev, "No memory left for err_skb\n"); - return; - } - - shhwtstamps = skb_hwtstamps(skb); - shhwtstamps->hwtstamp = hwtstamp; - - cf->can_id |= CAN_ERR_BUSERROR; - if (new_state != CAN_STATE_BUS_OFF) { - cf->can_id |= CAN_ERR_CNT; + shhwtstamps->hwtstamp = hwtstamp; + cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT; cf->data[6] = bec.txerr; cf->data[7] = bec.rxerr; + netif_rx(skb); + } else { + stats->rx_dropped++; + netdev_warn(netdev, "No memory left for err_skb\n"); } - netif_rx(skb); - priv->bec.txerr = bec.txerr; priv->bec.rxerr = bec.rxerr; } diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c index 6b9122ab1464..0491b4a6d8e8 100644 --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c @@ -1121,8 +1121,6 @@ static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev, const struct kvaser_usb_err_summary *es) { struct can_frame *cf; - struct can_frame tmp_cf = { .can_id = CAN_ERR_FLAG, - .len = CAN_ERR_DLC }; struct sk_buff *skb; struct net_device_stats *stats; struct kvaser_usb_net_priv *priv; @@ -1143,18 +1141,9 @@ static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev, if (!netif_running(priv->netdev)) return; - /* Update all of the CAN interface's state and error counters before - * trying any memory allocation that can actually fail with -ENOMEM. - * - * We send a temporary stack-allocated error CAN frame to - * can_change_state() for the very same reason. - * - * TODO: Split can_change_state() responsibility between updating the - * CAN interface's state and counters, and the setting up of CAN error - * frame ID and data to userspace. Remove stack allocation afterwards. - */ old_state = priv->can.state; - kvaser_usb_leaf_rx_error_update_can_state(priv, es, &tmp_cf); + skb = alloc_can_err_skb(priv->netdev, &cf); + kvaser_usb_leaf_rx_error_update_can_state(priv, es, cf); new_state = priv->can.state; /* If there are errors, request status updates periodically as we do @@ -1168,13 +1157,6 @@ static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev, schedule_delayed_work(&leaf->chip_state_req_work, msecs_to_jiffies(500)); - skb = alloc_can_err_skb(priv->netdev, &cf); - if (!skb) { - stats->rx_dropped++; - return; - } - memcpy(cf, &tmp_cf, sizeof(*cf)); - if (new_state != old_state) { if (es->status & (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET)) { @@ -1187,11 +1169,18 @@ static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev, if (priv->can.restart_ms && old_state == CAN_STATE_BUS_OFF && new_state < CAN_STATE_BUS_OFF) { - cf->can_id |= CAN_ERR_RESTARTED; + if (cf) + cf->can_id |= CAN_ERR_RESTARTED; netif_carrier_on(priv->netdev); } } + if (!skb) { + stats->rx_dropped++; + netdev_warn(priv->netdev, "No memory left for err_skb\n"); + return; + } + switch (dev->driver_info->family) { case KVASER_LEAF: if (es->leaf.error_factor) { -- 2.45.2